I am not a huge world traveler so I am sure there are many fine destinations that I am unaware of. However, in my limited experience, my favorite place in the world in Puerto Vallarta, Mexico. I know, it is a tourist resort, and the people depend on tourism for much of their economy. But after having spent a considerable amount of time there, I also know that the locals are some of the friendliest people I've ever met.
I've been elsewhere in the world where there always seems to be a barely hidden, simmering hostility toward Americans. (And truth be told, after witnessing some of the ridiculous behavior of a few other Americans abroad, I can sometimes sympathize.)
But the people in PV bring "friendly" to another level. They still go out of their way to welcome you and make you feel comfortable, even if they aren't making a sale.
And the fact that it's usually sunny and warm, as opposed to where I live, doesn't hurt either.
Before I pass though, I'd still like to visit Ireland to see if I can track down any distant relatives; and Italy to tour the wine country.